REISENBICHLER THICK OR THIN FERTILIZATION OF EGGS. 635 



best for obtaining as complete an impregnation of the eggs as possible. 

 Two persons, however, should always be employed, and the above-men- 

 tioned vessel should be used. The partial emptying of the milter is 

 always difficult and often a doubtful experiment. It will, therefore, be 

 best first to extract the roe from three spawners and empty the last 

 spawner at the same time as the milter in the manner above mentioned. 



Eoe and milt are usually mixed with the hand, which, however, should 

 not be done, as the warmth of the hand may easily injure the milt, and 

 as the mingling process will not be very thorough. If roe and milt are 

 not emptied into water the mingling process may be considerably facili- 

 tated by spreading the roe in broad layers and squeezing the milt evenly 

 over it. But for making the mingling thorough a sort of comb with blunt, 

 rounded-qf teeth should be employed, and the teeth should be far enough 

 apart to let the eggs pass through easily. Such combs are, properly 

 speaking, indispensable, if the impregnation is to be perfect. The comb 

 is several times drawn up and down through the roe and milt as soon as 

 tbey have been extracted and before they have been watered ; the neces- 

 sary quantity is then immediately added, best by letting it flow evenly 

 and rapidly from a watering-can with narrow apertures. The roe and 

 milt are then again mixed several times by means of the comb, which 

 will make the process of impregnation as complete as it is possible to 

 make it. 



All the above-mentioned operations must of course succeed each other 

 very rapidly. Special attention should be paid to the temperature; the 

 vessel destined to receive the roe and the milt, the comb and the water, 

 should all have the temperature of the fish, or rather of the roe and the 

 milt, and the use of the hands should therefore be avoided as much as 

 possible. The water should always be taken from that in which the fish 

 have previously lived. The weight of the water to be added should be 

 fully one-half that of the roe and milt. After having been mixed with 

 the comb the watery mixture should be left alone for about an hour in a 

 cool place, so the eggs may not get warm, and the impregnated eggs should 

 then be placed in the breeding-troughs with running water, which cleans 

 them of the milt which has now become useless.* 



* We have given the above article in its unaltered form, although we cannot entirely 

 agree with some of the opinions advanced by the author, while we must condemn 

 some of them. We therefore reserve our criticism for a future occasion. — Editor OF 

 Fischerei-Zeitung. 



